One type of switching circuit is a switching regulator. Switching regulators have high conversion efficiency and are therefore widely used as voltage converters in batteries for inputting voltage to a variety of control circuits (loads). For example, switching regulators are also widely used as on-board power supplies. In switching regulators, however, switching noise occurs during control to switch a switching circuit (MOSFET) on and off.
To address switching noise, one conventional approach uses a noise countermeasure. In greater detail, this conventional approach discloses attenuating resonance energy by turning a plurality of auxiliary switching elements, which each control the conduction current of high-side and low-side switching elements, on for a predetermined time period at a timing that matches the timing at which the switching elements are turned on. The switching elements and the auxiliary switching elements are controlled by corresponding driver circuits. One disadvantage of this conventional approach, however, is that it slows down the switching speed of the regulator.